CN108145114A - Blade casting method - Google Patents

Blade casting method Download PDF

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Publication number
CN108145114A
CN108145114A CN201611105149.1A CN201611105149A CN108145114A CN 108145114 A CN108145114 A CN 108145114A CN 201611105149 A CN201611105149 A CN 201611105149A CN 108145114 A CN108145114 A CN 108145114A
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CN
China
Prior art keywords
crucible
temperature
casting
mold
blade
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CN201611105149.1A
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Chinese (zh)
Inventor
曲立辉
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Qingdao Xiaomi Star Electronic Technology Co Ltd
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Qingdao Xiaomi Star Electronic Technology Co Ltd
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Priority to CN201611105149.1A priority Critical patent/CN108145114A/en
Publication of CN108145114A publication Critical patent/CN108145114A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D13/00—Centrifugal casting; Casting by using centrifugal force
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
    • C22F1/18—High-melting or refractory metals or alloys based thereon
    • C22F1/183—High-melting or refractory metals or alloys based thereon of titanium or alloys based thereon

Abstract

The invention discloses a kind of casting methods of blade, and using the method cast blade of hot investment casting, step includes mold design, mold manufacturing, raw material melting, blanking prepares, centrifugal casting, cools down for the first time, second of molding, second of cooling, trimming and sandblasting, hot isostatic pressing etc..The good elimination factor on engine blade surface and internal flaw ensure that by above-mentioned operation and interior microscopic tissue is more uniform.

Description

Blade casting method
Technical field
The present invention relates to casting fields, and in particular to the casting method of engine blade.
Background technology
Titanium alloy density is small, and specific strength is high, corrosion-resistant, due to this series of excellent characteristic, is widely used in boat Empty aerospace industry, energy industry, marine transportation industry etc..European Space Agency also once started aeronautical research plan, was exactly It is intended to grasp titanium aluminium base alloy blade of aviation engine and gas turbine blades.Aircraft engine thrust-weight ratio is evaluation modern aircraft One of leading indicator of engine, it has aeroplane performance conclusive effect.When being currently applied to engine blade, Relatively conventional forming method is casting method.TiAl-base alloy component is prepared using investment precision casting technology, especially It is complex-shaped component, can obtain the accurate complex component of no surplus or Near net shape, metal loss is greatly reduced, improves The utilization rate of material reduces a large amount of machining working hours, production cost is greatly lowered.
At present using more titanium alloy precision casting shell, it is broadly divided into：Graphite shell, tungsten face layer ceramic mould Shell, New Oxide Ceramic Shell Mould etc..But it since the deficiency of mold generation type and the parameter designing of casting process are unreasonable, leads Piece surface after molding and internal flaw is caused to compare more.
Invention content
It is an object of the invention to propose a kind of casting method of blade；For this purpose, the present invention uses following technology Scheme：A kind of casting method of blade, including mold design, mold manufacturing, raw material melting, blanking prepares, centrifugal casting, and first Secondary cooling, second of molding, second of cooling, trimming and sandblasting, hot isostatic pressing step；The blade is engine blade, Material be titanium aluminium niobium alloy, the titanium aluminium niobium alloy composition by weight percentage for 45~48% aluminium, 5~6.8% niobium, 3.1~4.2% magnesium, V：1.2~1.5%, Ta：0.002~0.008%, 0.10~0.28% carbon, surplus are titanium and can not The impurity avoided；
The step of mold design is, using water-soluble core, to design to obtain engine blade using existing CAD system CAD model, rapid shaping is carried out using existing quick shaping process, laser sintered successively sintering diameter is poly- less than 0.1mm Styrene powder, then fusible pattern is made after waxdip, surface and internal cleaning then are carried out to fusible pattern；
The step of mold manufacturing is fusible pattern to be immersed in investment precoat after being stained with 30~45s of slurry to take out, and is then carried out Stucco, the drying of face layer, obtain formwork, formwork are put into heating furnace, and 2.5~3h is kept the temperature in being 380~500 DEG C in temperature, It is 820~870 DEG C to then proceed to heating, keeps the temperature 2.5~3h, and it is 1050~1150 DEG C to continue heating, keeps the temperature 2.5~3h, then Furnace cooling obtains mold to room temperature；
The step of raw material melting is that the raw material for treating melting are put into crucible, and crucible is placed in vaccum sensitive stove Crucible for smelting room in, the flushing of 4~8 times is first carried out to crucible for smelting room using inert gas, it is final to keep crucible for smelting room Vacuum degree be 10-5~10-3Mbar carries out melting, keeps the temperature 10~15min after the completion of melting so that each element in raw material is equal It is even；
The step of blanking prepares is the mold obtained with asbestos package mold manufacturing step, blanking after being preheated, The temperature of the preheating is 400~610 DEG C；
The technological parameter of the centrifugal casting is that centrifugal rotational speed is 195rpm~385rpm, and casting time is 6~8s；
The step of first time cooling is to come out of the stove air-cooled, and after core is dissolved out, cleaning part is simultaneously dried；Described second The step of secondary molding, which is that the casting obtained after first time is cooled down is put into, to be preheating in 910~990 DEG C of mold, is then being added 1050~1150 DEG C are heated in hot stove, then carries out centrifugal casting, centrifugal rotational speed is 195rpm~385rpm；Described second The step of cooling be come out of the stove it is air-cooled；The step of trimming and sandblasting is shell to be removed using mechanical means, by casting system Excision cuts away technique edges with high pressure water, carries out blasting treatment；
The step of hot isostatic pressing is that the temperature of hot isostatic pressing is 950~990 DEG C, the pressure 100 of hot isostatic pressing~ 180MPa, dwell time are 3~6 hours.
Preferably, the crucible is water jacketed copper crucible.
Preferably, the flushing that the inert gas carries out crucible for smelting room 4~8 times is, first by crucible for smelting room It is evacuated to 10-5~10-3Mbar is then charged with argon gas to 10~14mbar, is then evacuated to 10 again-5~10-3Mbar, such as This is totally 4~8 times repeatedly.
Preferably, the investment precoat for zirconium oxide, two acetic acid zirconiums, fatty alcohol polyoxyethylene ether and n-butanol by stirring Obtained from mixing, standing.
Preferably, zirconium oxide in the investment precoat, two acetic acid zirconiums, fatty alcohol polyoxyethylene ether and n-butanol weight Part ratio is 3.8~4.2：1：0.0004~0.001：0.0006~0.0012.
Preferably, the raw material for treating melting are fine aluminium, niobium aluminium, pure carbon, magnalium intermediate alloy and titanium sponge.Make To be preferred, annealing steps are further included after hot isostatic pressing, the annealing steps are in annealing furnace by the blade after hot isostatic pressing In be heated to 680~710 DEG C, after keeping the temperature 60~180min, come out of the stove air-cooled until room temperature.
Effect of the invention is that：Pass through specific mold manufacturing and design process so that mold meets engine blade Particular demands；Pass through the setting of centrifugal casting parameter so that internal flaw is eliminated well；Pass through post forming and two Secondary cooling so that interior tissue is uniform and stable and internal flaw is caused to obtain extraordinary elimination, and ensure that surface defect Good elimination factor；The setting of hot isostatic pressing parameter so that interior microscopic tissue is more uniform；Pass through specific temperature and time Annealing so that engine blade have good intensity and toughness.
Specific embodiment
Embodiment 1
The casting method of blade, including mold design, mold manufacturing, raw material melting, blanking prepares, centrifugal casting, and first Secondary cooling, second of molding, second of cooling, trimming and sandblasting, hot isostatic pressing step；
The blade be engine blade, material be titanium aluminium niobium alloy, the composition by weight hundred of the titanium aluminium niobium alloy Divide aluminium, 5.8% niobium, 3.8% magnesium, the V than being 46%：1.25%, Ta：0.0028%th, 0.18% carbon, surplus for titanium and Inevitable impurity；
The step of mold design is, using water-soluble core, to design to obtain engine blade using existing CAD system CAD model, rapid shaping is carried out using existing quick shaping process, laser sintered successively sintering average diameter is 0.08mm Fusible pattern is made after polystyrene powder, then waxdip, surface and internal cleaning then are carried out to fusible pattern；
The step of mold manufacturing be fusible pattern is immersed in investment precoat be stained with slurry 35s after take out, then carry out face layer Stucco, drying, obtain formwork, formwork be put into heating furnace, in temperature to keep the temperature 2.6h in 480 DEG C, then proceed to heat up It is 850 DEG C, keeps the temperature 2.8h, it is 1060 DEG C to continue heating, keeps the temperature 2.7h, then furnace cooling to room temperature, obtains mold；The face Coating is zirconium oxide, two acetic acid zirconiums, fatty alcohol polyoxyethylene ether and n-butanol as obtained from stirring, stand；Its weight Part ratio is 3.9：1：0.0008：0.0009；
The step of raw material melting is that the raw material for treating melting are put into water jacketed copper crucible, the original for treating melting Material is fine aluminium, niobium aluminium (niobium aluminium intermediate alloy), pure carbon, magnalium intermediate alloy and titanium sponge；Crucible is placed in vacuum induction In the crucible for smelting room of stove, the flushing of 6 times is first carried out to crucible for smelting room using inert gas, first vacuumizes crucible for smelting room To 10-5Mbar is then charged with argon gas to 12mbar, is then evacuated to 10 again-5Mbar, so repeatedly totally 6 times；It is final to keep The vacuum degree of crucible for smelting room is 3x 10-4Mbar carries out melting, keeps the temperature 14min after the completion of melting so that each element in raw material Uniformly；
The step of blanking prepares is the mold obtained with asbestos package mold manufacturing step, blanking after being preheated, The temperature of the preheating is 510 DEG C；
The technological parameter of the centrifugal casting is centrifugal rotational speed 285rpm, casting time 7s；The first time cooling The step of be come out of the stove it is air-cooled, after core is dissolved out, cleaning part simultaneously dry；The step of second of molding, is, by first time The casting obtained after cooling, which is put into, to be preheating in 985 DEG C of mold, is then heated to 1080 DEG C in heating furnace, then carry out from The heart is cast, centrifugal rotational speed 355rpm；Described second cold step be come out of the stove it is air-cooled；The step of trimming and sandblasting is, Shell is removed using mechanical means, casting system is cut off, technique edges is cut away with high pressure water, carries out blasting treatment；Described heat etc. The step of static pressure is that the temperature of hot isostatic pressing is 980 DEG C, and the pressure of hot isostatic pressing is 160MPa, and the dwell time is small for 4.5 When.
Embodiment 2：
The casting method of blade, including mold design, mold manufacturing, raw material melting, blanking prepares, centrifugal casting, and first Secondary cooling, second of molding, second of cooling, trimming and sandblasting, hot isostatic pressing step；The blade is engine blade, Material is titanium aluminium niobium alloy, and the composition of the titanium aluminium niobium alloy is by weight percentage 48% aluminium, 5.9% niobium, 3.7% Magnesium, V：1.35%, Ta：0.006%th, 0.28% carbon, surplus are titanium and inevitable impurity；
The step of mold design is, using water-soluble core, to design to obtain engine blade using existing CAD system CAD model, rapid shaping is carried out using existing quick shaping process, laser sintered successively sintering average diameter is 0.09mm Fusible pattern is made after polystyrene powder, then waxdip, surface and internal cleaning then are carried out to fusible pattern；
The step of mold manufacturing be fusible pattern is immersed in investment precoat be stained with slurry 38s after take out, then carry out face layer Stucco, drying, obtain formwork, formwork be put into heating furnace, in temperature to keep the temperature 2.8h in 490 DEG C, then proceed to heat up It is 860 DEG C, keeps the temperature 2.7h, it is 1055 DEG C to continue heating, keeps the temperature 2.8h, then furnace cooling to room temperature, obtains mold；The face Coating is zirconium oxide, two acetic acid zirconiums, fatty alcohol polyoxyethylene ether and n-butanol as obtained from stirring, stand；Its weight Part ratio is 4.0：1：0.0009：0.0008；
The step of raw material melting is that the raw material for treating melting are put into water jacketed copper crucible, the original for treating melting Material is fine aluminium, niobium aluminium (niobium aluminium intermediate alloy), pure carbon, magnalium intermediate alloy and titanium sponge；Crucible is placed in vacuum induction In the crucible for smelting room of stove, the flushing of 5 times is first carried out to crucible for smelting room using inert gas, first vacuumizes crucible for smelting room To 10-4Mbar is then charged with argon gas to 11mbar, is then evacuated to 10 again-4Mbar, so repeatedly totally 5 times；It is final to keep The vacuum degree of crucible for smelting room is 5x 10-4Mbar carries out melting, keeps the temperature 18min after the completion of melting so that each element in raw material Uniformly；
The step of blanking prepares is the mold obtained with asbestos package mold manufacturing step, blanking after being preheated, The temperature of the preheating is 520 DEG C；
The technological parameter of the centrifugal casting is centrifugal rotational speed 295rpm, casting time 10s；The first time is cold But the step of be come out of the stove it is air-cooled, after core is dissolved out, cleaning part simultaneously dry；The step of second of molding, is, by first The casting obtained after secondary cooling, which is put into, to be preheating in 995 DEG C of mold, is then heated to 1070 DEG C in heating furnace, is then carried out Centrifugal casting, centrifugal rotational speed 365rpm；Described second be the step of cooling come out of the stove it is air-cooled；The trimming and the step of sandblasting Suddenly it is that shell is removed using mechanical means, casting system is cut off, cuts away technique edges with high pressure water, carry out blasting treatment；It is described The step of hot isostatic pressing is that the temperature of hot isostatic pressing is 990 DEG C, and the pressure of hot isostatic pressing is 165MPa, the dwell time 4.6 Hour.
Embodiment 3：The casting method of blade, including mold design, mold manufacturing, raw material melting, blanking prepares, centrifugal casting It makes, cools down for the first time, second of molding cools down, trimming and sandblasting, hot isostatic pressing step for the second time；The blade is engine Blade, material are titanium aluminium niobium alloy, aluminium by weight percentage for 45.2% of the composition of the titanium aluminium niobium alloy, 6.0% Niobium, 3.9% magnesium, V：1.45%, Ta：0.0068%th, 0.38% carbon, surplus are titanium and inevitable impurity；The mould The step of tool design is, using water-soluble core, to design to obtain the CAD model of engine blade using existing CAD system, is used Existing quick shaping process progress rapid shaping, the polystyrene powder that laser sintered successively sintering average diameter is 0.07mm, then Fusible pattern is made after waxdip, surface and internal cleaning then are carried out to fusible pattern；The step of mold manufacturing is to immerse fusible pattern It is taken out after slurry 42s is stained with into investment precoat, then carries out stucco, the drying of face layer, obtain formwork, formwork is put into heating furnace In, 2.6h is kept the temperature in being 490 DEG C in temperature, it is 850 DEG C to then proceed to heating, keeps the temperature 2.6h, and it is 1052 DEG C to continue heating, heat preservation 2.6h, then furnace cooling to room temperature, obtains mold；The investment precoat is zirconium oxide, two acetic acid zirconiums, aliphatic alcohol polyethenoxy Ether and n-butanol are as obtained from stirring, stand；Its weight ratio is 4.1：1：0.0007：0.0007；The raw material melts The step of refining is that the raw material for treating melting are put into water jacketed copper crucible, and the raw material for treating melting are fine aluminium, niobium aluminium (niobium aluminium intermediate alloy), pure carbon, magnalium intermediate alloy and titanium sponge；Crucible is placed in the crucible for smelting room of vaccum sensitive stove, The flushing of 4 times is first carried out to crucible for smelting room using inert gas, crucible for smelting room is first evacuated to 10-4Mbar, Ran Houchong Enter argon gas to 11mbar, be then evacuated to 10 again-4Mbar, so repeatedly totally 4 times；The final vacuum degree for keeping crucible for smelting room It is 10-4Mbar carries out melting, keeps the temperature 19min after the completion of melting so that each element in raw material is uniform；
The step of blanking prepares is the mold obtained with asbestos package mold manufacturing step, blanking after being preheated, The temperature of the preheating is 530 DEG C；
The technological parameter of the centrifugal casting is centrifugal rotational speed 298rpm, casting time 11s；The first time is cold But the step of be come out of the stove it is air-cooled, after core is dissolved out, cleaning part simultaneously dry；The step of second of molding, is, by first The casting obtained after secondary cooling, which is put into, to be preheating in 994 DEG C of mold, is then heated to 1072 DEG C in heating furnace, is then carried out Centrifugal casting, centrifugal rotational speed 368rpm；Described second be the step of cooling come out of the stove it is air-cooled；The trimming and the step of sandblasting Suddenly it is that shell is removed using mechanical means, casting system is cut off, cuts away technique edges with high pressure water, carry out blasting treatment；
The step of hot isostatic pressing is that the temperature of hot isostatic pressing is 992 DEG C, and the pressure of hot isostatic pressing is 168MPa, Dwell time is 4.8 hours.

Claims (5)

1. a kind of casting method of blade, which is characterized in that including mold design, mold manufacturing, raw material melting, blanking prepares, Centrifugal casting cools down for the first time, and second of molding cools down, trimming and sandblasting, hot isostatic pressing step for the second time；The blade is Engine blade, material be titanium aluminium niobium alloy, the titanium aluminium niobium alloy composition by weight percentage for 45~48% aluminium, 5~6.8% niobium, 3.1~4.2% magnesium, V：1.2~1.5%, Ta：0.002~0.008%, 0.10~0.28% carbon, Surplus is titanium and inevitable impurity；The step of mold design, is, using water-soluble core, using existing CAD system Design obtains the CAD model of engine blade, and rapid shaping is carried out using existing quick shaping process, laser sintered to be successively sintered Diameter is less than the polystyrene powder of 0.1mm, then fusible pattern is made after waxdip, then carries out surface and internal cleaning to fusible pattern；Institute The step of stating mold manufacturing is fusible pattern to be immersed in investment precoat after being stained with 30~45s of slurry to take out, and then carries out spreading for face layer Sand is dried to obtain formwork, and formwork is put into heating furnace, keeps the temperature 2.5~3h in being 380~500 DEG C in temperature, then proceedes to rise Temperature is 820~870 DEG C, keeps the temperature 2.5~3h, and it is 1050~1150 DEG C to continue heating, keeps the temperature 2.5~3h, and then furnace cooling is arrived Room temperature obtains mold；The step of raw material melting is that the raw material for treating melting are put into crucible, and crucible is placed in vacuum In the crucible for smelting room of induction furnace, the flushing of 4~8 times is first carried out to crucible for smelting room using inert gas, finally keeps crucible The vacuum degree of working chamber carries out melting for 10-5~10-3mbar, keeps the temperature 10~15min after the completion of melting so that each in raw material Element is uniform；The step of blanking prepares is the mold obtained with asbestos package mold manufacturing step, after being preheated under Material, the temperature of the preheating is 400~610 DEG C；The technological parameter of the centrifugal casting is, centrifugal rotational speed for 195rpm~ 385rpm, casting time are 6~8s；The step of first time cooling is to come out of the stove air-cooled, after core is dissolved out, cleans part And it dries；Described second is to be put into the casting obtained after first time cooling and be preheating to 910~990 DEG C the step of molding In mold, be then heated to 1050~1150 DEG C in heating furnace, then carry out centrifugal casting, centrifugal rotational speed for 195rpm~ 385rpm；Described second be the step of cooling come out of the stove it is air-cooled；The step of trimming and sandblasting, is, clear using mechanical means Except shell, casting system is cut off, technique edges is cut away with high pressure water, carries out blasting treatment；The step of hot isostatic pressing is heat The temperature of isostatic pressed is 950~990 DEG C, and the pressure of hot isostatic pressing is 100~180MPa, and the dwell time is 3~6 hours.
2. the casting method of blade according to claim 1, which is characterized in that the crucible is water jacketed copper crucible.
3. the casting method of blade according to claim 1, which is characterized in that the inert gas is to crucible for smelting room The flushing for carrying out 4~8 times is that crucible for smelting room first is evacuated to 10-5~10-3Mbar, be then charged with argon gas to 10~ Then 14mbar is evacuated to 10 again-5~10-3Mbar, so repeatedly totally 4~8 times.
4. the casting method of blade according to claim 1, which is characterized in that the investment precoat is zirconium oxide, two vinegar Sour zirconium, fatty alcohol polyoxyethylene ether and n-butanol are as obtained from stirring, stand.
5. the casting method of blade according to claim 4, which is characterized in that zirconium oxide, two vinegar in the investment precoat The weight ratio of sour zirconium, fatty alcohol polyoxyethylene ether and n-butanol is 3.8~4.2：1：0.0004~0.001：0.0006~ 0.0012。
CN201611105149.1A 2016-12-05 2016-12-05 Blade casting method Pending CN108145114A (en)

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Application Number Priority Date Filing Date Title
CN201611105149.1A CN108145114A (en) 2016-12-05 2016-12-05 Blade casting method

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Application Number Priority Date Filing Date Title
CN201611105149.1A CN108145114A (en) 2016-12-05 2016-12-05 Blade casting method

Publications (1)

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CN108145114A true CN108145114A (en) 2018-06-12

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